Ralway switch operating mechanism



Dec. 26, 1939. H; L. BONE HAL 2,184,870

RAILWAY SWITCH OPERATING MECHANISM Filed Oct. 20, 1937 4 Sheets-Sheet l Fly! THEIR ATTORNEY Dec. 26, 1939. H. l., BONE l=:r Al. 2,184,870

RAILWAY SWITCH OPERATING MECHANISM Filed oct. 2o, 1957 4 sheets-sheet 2 THEIR ATTORNEY Dec. 26, 1939. H. BONE ET AL RAILWAY SWITH OPERATING MECHANISM Filed oct. z, 193? 4 sheets-sheet 3 INVENTORS- Herber one and Kennet J M06 an THEIR ATToRNEY Jlb Z9 1150.

Dec. 26, 1939. H. L. BONE ET AL 2,184,870

RAILWAY SWITCH OPERATING MECHANISM Filed Oct. 20, 1957 4'Sheets-Sheet 4 Fig. I0

I Main Track N Siding Main Twaalf Fly. I4

Main Tkach4 l5 Fly. f N 115 115 i I lNvENToRs Herbert Bone and Hgfe f JMcGow rz THER ATTORNEY Patented Dec. 26, 1939 STATES PATENT OFFiCE RAILWAY SWITCH OPERATING IVIECHANISM Application October 20, 1937, Serial No. 170,060

6 Claims.

Our invention relates to railway switch operating mechanisms, and particularly to improvements in mechanisms of the type shown and described in Letters Patent of the United States No. 1,654,023, granted to C. C. Thorn for Switch throwing and locking mechanism, on December 27, 1927.

One object of our invention is to provide a mechanism of the type described which is capable of operating the heavier and therefore stiier switches now being employed, and which has a high overall eiciency.

Another object of our invention is to provide a mechanism of the type described which is economical to build and maintain.

A further object of our invention is to provide a mechanism of the type described which reachly adapts itself to use with either a righthand or a left-hand switch layout regardless of whether the point adjacent the mechanism is normally closed or normally open.

A still further object of our invention is to provide a novel circuit controller for detecting the position oi' the switch points.

Other objects and characteristic features of our invention will appear as the description proceeds.

We shall describe two forms of railway switch operating mechanisms embodying our invention, and shall then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a view showing a railway switch operated by a switch operating mechanism embodying our invention. Fig. 2 is an enlarged top plan view of the switch operating mechanism shown in Fig. 1, the cover of the mechanism being removed and some of the parts being shown in section to better illustrate the construction of the remaining parts. Fig. 3 is a vertical longitudinal sectional View of the mechanism shown in Fig. 2 taken substantially on the line III-III of Fig. 2. Fig. 4 is a sectional view taken substantially on the line )IV-IV of Fig. 3. Figs. 5, 6, and 7 are detail views of various parts of the mechanism shown in the preceding views. Figs. 8 and 9 are detail views showing modiiications of a portion of the mechanism shown in the preceding views. Figs. 10 and 11 are diagrammatic views showing the application of a switch operating mechanism embodying our invention to a single switch leading to a siding which is provided with a derail. Figs. 12 and 13 are diagrammatic views showing a crossover layout wherein a certain sequence of operation of the two ends is enforced by means of .bolt

switch operating mechanisms embodying our invention. Figs. 14, 15, and 16 are diagrammatic views showing another crossover layout provided with switch operating mechanisms embodying our invention. Similar reference characters refer parts in each of the several views.

Referring iirst to Fig. 1, thereference character A designates a railway switch comprising, as usual, two xed rails I and Ia and two movable rails or switch points 2 and 2a. The fixed rails I and Ia are laid on tie plates t, and are secured to crossties 4 in the customary manner. The movable rails 2 and 2c are fastened together by a front rod 5 and a head rod 6, and may be moved into a normal or a reverse position by means of a throw rod l which is connected with ,the head rod 6 through the medium of a switch basket 8. When the switch occupies its normal position, in which position it is shown in the drawings, themovable rail 2 engages the iixed rail i, and the movable rail 2a. is spaced from the iixed rail Ia. When the switch is reversed, however, the movable rail 2a then engages the xed rail Ia, and the movable rail 2 is spaced from the fixed rail l.

Secured to -an elongated pair of the ties 4 adjacent the outer side of the rail I is a switch operating mechanism B embodying our invention, which mechanism we shall now describe. As best seen in Figs. 2, 3, and 4, the mechanism B, in the form here shown, comprises a suitable casing Mi which encloses the operating parts of the mechanism, and which is closed at its upper end by a removable cover li. The cover il is held in place at its right-hand end by means of a U-bolt I2 which overlies iingers I4 cast on the cover, and at its left-hand end by an adjustable haspl I8. rlhe U-bolt i2 is secured to lugs I3 cast on the sides of the casing l0, by means of nuts l5 disposed above the lugs, and other nuts i6 disposed below the lugs, the lower nuts ,being made square, and being seated in a recess formed by depending projections i3d provided on the lugs, whereby it is impossible to remove the nuts I6 without rst removing the cover, and then backing off the upper nuts i5 a suiiicient amount.

The adjustablehasp i8 comprises astrap '18a pivotally attached by means of `a pin Ib to a nut itc screwed onto the upper end of a T-headed 19d. The bolt ltd extends downwardly through a hole in a lug I9 provided on the cover, and coperates at its head with a pair of iingers 20 formed on the left-hand end wall of the casing lo. The strapy Ia. slips over a hasp eye. 2l secured to the cover I I, thereby permitting the parts to be to similar locked in place by a padlock or the like. To fasten the cover in place the fingers I4 are first inserted under the U-bolt I 2, and the head of the bolt I8d is then placed under the fingers 20. The nut is next tightened by using the strap l8a as a means for turning the nut, after which the strap is dropped over the eye 2| and a padlock is inserted through the eye. To remove the cover, the opposite procedure is followed. It will be obvious, of course, that when the cover is unfastened, it can be readily lifted clear of the casing, thus permitting ready access to the operating parts of the mechanism. To insure a good seal between the cover and the casing, the cover is formed with a peripheral groove containing packing 23 which seals against the casing.

Located within the casing lil of the mechanism B is a motion plate 25 (see Fig. 5) which is guided to slide longitudinally in a direction parallel to the track by means of, guide rollers 25 and 21 secured to the underside of the motion plate adjacent its opposite ends and cooperating with guideways 28 provided on the bottom wall of the casing. The motion plate 25 has rack teeth 25 formed in its upper surface on one side of the center line, the spaces between the teeth being disposed below the adjacent upper surface of the plate, and being curved inwardly at their ends for a purpose which will be made clear presently. The rack teeth 29 mesh with a segment gear 36 mounted on a square shaft 3|, which shaft, in turn, is mounted at its ends in bearing sleeves 32 and 33 journaled in bosses 34 and 35 formed in the side walls of the casing Ill. The bearing Sleeve 32 is provided at its outer end with a flange 32a, and is` secured to the shaft 3l by means of a through bolt 36. The bearing sleeve 33 is also provided at its outer end with a flange 33a, and secured to the shaft 3l adjacent the flange 33a by means of a through bolt 3l is a hand-throw lever 38 which serves as a means for reciprocating the motion plate 25 between its two extreme positions. The segment gear 3l? is slidably mounted on the shaft 3| with enough clearance so that it can be readily slipped olf the shaft. and has its teeth curved at their ends in a manner similar to the ends of the spaces between the rack teeth, whereby the segment gear is maintained in the proper longitudinal position on the shaft to mesh with the rack teeth by the cam action which results between the curved ends of the teeth on the gear and the curved ends of the spaces between the rack teeth, thus eliminating the necessity for any means for securing the segment gear to the shaft. One advantage of this construction is that the shaft can be turned end for end to permit the mechanism to be mounted on the opposite side of the switch from that shown without unfastening any of the parts from the shaft but the bearing sleeve 32.

A roller 40 is secured to the underside of the motion plate 25 adjacent one side thereof at a point equally spaced from the rollers 2G and 2l, and this latter roller cooperates with cam faces 4I and 42 formed on an escapement crank 43 (see Fig. 2). The escapement crank 43 is formed integrally with the upper end of a switch actuating shaft 44, the shank of which is provided with two bearing surfaces 45 and 45 separated by a squared portion 4l. The bearing surfaces 45 and 46 are journaled in vertically aligned bearings 48 and 49 formed respectively in the bottom of the casing ID, and in a depending stirrup 50 which is provided on the underside of the casing, and secured to the square portion 4l of the shaft is a removable switch operating arm 50a which is pivotally attached to the free end of the throw rod '1.

A lock bar 5I extends longitudinally of the casing lll directly above the motion plate 25, and is slidably mounted adjacent one end in a guide plate 52 bolted to the end wall of the casing in a position to close an opening 53 through which the slide bar extends with considerable clearance. The other end of the lock bar is slidably mounted in a guideway 54 (see Figs. 3 and 4) formed in a frame 55 which is bolted to the casing Hl adjacent its left-hand end by means of four bolts 56,'and which serves as a support for a circuit controller, as will appear hereinafter. The lock bar is operatively connected with the motion plate by means of a stud 5l secured to the lock bar and extending into a transversely extending slot 58 formed in the upper side of the motion plate. The parts are so proportioned that when the guide plate 52 is secured to the casing lll, the stud 5l will be held in operative engagement with the slot 58, but that, when the guide plate 52 is unbolted from the casing, the stud can be lifted clear of the slot 58 and the lock bar can be removed from the casing through the opening 53.

The left-hand end of the lock bar 5i cooperates with a notch 59 provided in a lock rod L which is secured to the front rod 5. The parts are so proportioned that the notch 59 will align with the lock bar when and only when the switch occupies its full normal position, and that, when the notch 59 is in alignment with the lock bar, and the motion plate is in its left-hand extreme position, the lock bar will have entered the notch 59, as shown in Fig. 3, and will thus have locked the switch in its normal position.

The operation, as a whole, of the portion of the apparatus thus far described is as follows: When the hand-throw lever 38 is rotated to its normal extreme position in which it is shown in the drawing, the motion plate 25 is moved to its extreme left-hand or normal position in which it is shown in Figs. 2 and 3, and under these conditions, the switch points are held in their normal positions by engagement of the roller 4i) with the cam surface 4l of the escapement crank 43. Furthermore, under these conditions, the lock bar 5| enters the notch 59 in the lock rod L, thus locking the switchpoints in their normal positions.

When it is desired to reverse the switch, the hand-throw lever 38 is rotated in a counterclockwise direction through an angle of substantially from the extreme position shown to its opposite or reverse extreme position. This rotation of the hand-throw lever acts through the segment gear 35 and rack teeth 29 to move the motion plate to its right-hand extreme position, and as the motion plate moves to this latter position, the first part of the movement withdraws the lock bar 5I from the notch 59 in the lock rod L to unlock the switch, the intermediate part of the movement causes the roller 40 to engage the cam surface 42 of the escapement crank 43 and rotate the escapement crank to the position in which the straight portion of the cam surface 42 extends parallel to the track, thereby rotating the switch actuating shaft to its reverse eXtreme position, and hence moving the switch points to their reverse extreme positions, while the final part of the movement of the motion plate causes the roller 40 to move along the straight portion of the cam surface 42 to such a position that any tendency of the switch actuating shaft to rotate in a direction to permit the switch points to move away from their reverse positions is electively blocked by the roller. It will be seen, therefore, that when the switch points occupy their reverse extreme positions, they are effectively held in these positions due to the coaction between the roller and the escapement crank, and it will .also be seen that any force which may be exerted on the switch tending to restore it to its normal position will cause a transverse force to be exerted onthe motion plate rather than a longitudinal `force, thus avoiding any'. tendency toreverse the hand-throw lever due to any force which may be exerted on the switch.

When the switch has been moved to its reverse position, and it is desired to restore it to its normal position, the hand-throw lever SSis returned to the position shown. The operation of the parts under these conditions is exactly the reverse of that just described, and this operation will be apparent from the foregoing description and from an inspection of the drawings without further detailed description. v

A bearing plate 6U is bolted tothe upper side of the casing Ill adjacent its right-hand end, and journaled in a vertical bearing Si fo-rmed in this bearing plate is a target staff 62, the lower end of which carries a crank 63. The crank 53 is provided with a depending pin or cam follower Sil which extends into, and cooperates with, a cam slot 55 formed in the upper face of the motion plate 25, whereby movement of the motion plate between its two extreme positions will rotate the target staff through an angle of 90. The upper end of the target stai is intended to be provided with suitable signaling means here shown as the usual target 62o (see Fig. 1), and in order to permit the target to be turned to the desired position with respect to the track, the lower end of the staff 52 and the hub of the target crank 53 are provided with matching serrations, whereby by changing the relative position of the serrations on the staff and on the crank different positions of the shaft with respect to the motion plate for any given position of the motion plate can be obtained. The crank is secured to the target sta by means of a clamping bolt t5 which extends through aligned holes formed in split portions of the hub of the crank and engages a groove 52a formed in the lower end of the target staff. The target staff is maintained in the proper vertical position by the hub of the crank and-by a shoulder 62h which is formed on the staff, and which cooperates with the upper end of the bearing 6I in the bearing plate B0.

Under certain conditions which will be made clear hereinafter, the motion plate is turned end for end, and in order to permit the target staff to be operated under these conditions, the motion plate is provided in its upper side with another cam slot 65a whichV is similar to, but oppositely disposed from, the cam slot 65.

In the event that it is not desired to provide the mechanism with a target, the opening in the casing l@ which is closed by the bearing plate SEI when the target is provided may then be closed by a blank plate bolted to the casing in the saine manner that the bearing plate is bolted to the casing.

The mechanism may also include a suitable circuit controller for controlling signals for governing the movement of trahie over the switch. As shown in the drawings, this circuit controller comprises a rocker arm 'HJ (see Figs. 2, 3 and '7) pivotally supported intermediate its ends on a pin 1l secured within a pair of spaced upstanding lugs 72 provided on the frame 55, The rocker arm ll is disposed directly above the lock bar 5l, and is provided with a cam face 'lila which cooperates with a cam face 73a provided on a cam dog 'I3 secured to the upper side of the lock bar 5i in such manner that when the lock bar is moved to the position in which it is withdrawn from the notch 59 in the lock rod L the cam face 73a, will engage the cam face '10a shortly before the lock bar has cleared the notch and will positively rotate the rocker arm in a counterclockwise direction, as viewed in Fig. 3, from its normal extreme position toi a reverse extreme position. The rocker arm is also provided with a cam face lb which joins the right-hand end of the cam face 70a, and which cooperates with the top of the lock dog to maintain the rocker arm in its reverse extreme position whenever the switch is unlocked.

A contact operating member l5 (see Fig. 4) is pivotally attached to the left-hand end of the rocker arm lll, and is guided to move vertically by means of upwardly extending studs l'S which are provided on the frame 55, and which pass freely through clearance holes Tl formed in the operating member.' Surrounding the studs 'it between the frame and the contact operating member are compressed coil springs TB, whereby the operating member is biased to an upper posi-- tion in which it engages adjustable stop nuts i9 screwed onto the upper ends of the studs, it being noted that since the contact operating member is pivotally attached to the rocker arm lil, the springs I8 also serve to bias the rocker arm to its normal position in which it is shown in Fig. 3. Two superposed insulating blocks t@ and Si are secured to the upper side of the operating member, and extending between these blocks are the free ends of a plurality of flexible contact fingers 82, here shown as four in number. Each contact finger 82 cooperates with a xed contact member 83 to form a contact 82--83- Each contact linger 82 and the associated contact member 83 are clamped to the opposite sides of an insulating block 84 by means of terminal posts 85 and 86, and the insulating block 8d, in turn, is supported on lugs 8l projecting upwardly from the frame 55. Each terminal post 85 is electrically connected with the associated contact nger 82, but is insulated from the associated contact member 33, as will be apparent from an inspection of the drawings; while each terminal post 8G is electrically connected with the associated contact member 83, but is insulated from the associated contact nger 82. The parts are so proportioned that when the rocker arm 'lil occupies its normal extreme position which it is shown in the drawings, each Contact 82-33 will be open, but that, when the rocker arm is rotated to its other extreme position, each contact 32-83 will then be closed. It will be apparent, therefore, that the contacts 32--83 will become closed whenever the lock bar is withdrawn from the notch 59 in the lock rod L to unlock the switch.

It should be pointed out that the contact finger 82 and contact member 83 which comprise each contact may, if desired, be reversed to provide a normally closed instead of a normally open contact.

t should also be pointed out that by adjusting the stop nuts 'I9 the positions to which the contact operating member 'I5 and rocker arm 'IEB are biased can be varied, thus eliminating any necessity for individual contact adjustment and also permitting adjustment to be made for slight manufacturing variations.

The circuit controller also comprises a point detector lever 99 (see Figs, 4 and 6) which is pivotally supported on a pin 9| mounted in the frame 55, and which is biased, by means of a spring 92 interposed between the frame anda laterally projecting latch arm 93 the function of which will be made clear presently, in a counterclockwise direction to the position in which a roller 94 mounted in a depending lug 95 formed on the point detector lever enters a notch 96 in a point detector rod D. The point detector rod D is slidably mounted in the casing Iii, and as shown in Fig. 1 is attached, by means of a link 9i and a bolt 98 to the movable rail 2 of the switch A in the usual and well-known manner. The point detector lever 9G is also provided with a laterally projecting arm 99 having a rounded end lil() which overlies and cooperates with the conical head Mila of a ringer IBI which is adjustably mounted in an upstanding lug lilc provided on the rocker arm 1Q. The notch 96 in the point detector rod D is so disposed and the parts are so proportioned that the roller 99 will enter the notch when and only when the movable rails 2 and 2o of the switch A occupy their normal extreme positions and the movable rail 2 is in proper engagement with the fixed rail I. The parts are further so proportioned that when the roller 94 is within the notch 9B and the rocker arm IB occupies its normal position, the rounded end Hill of the point detector lever will just touch the upper side of the conical head Illia of the finger II, but that, when the roller 94 is forced out of the notch 96, the resultant clockwise rotation of the point detector lever will cause the rounded end lili) of the point detector lever to cooperate with the head IOIa of the iinger illI in a manner to rotate the rocker arm 'I0 to its reverse extreme position, thus causing the contacts 82-83 to become closed. It follows, therefore, that any displacement of the switch point 2 away from the rail I when the parts are in the positions shown in the drawings will operate the contacts 82-83.

It should be noted that the depending lug 95 which supports the roller 94 is disposed adjacent one end of the point detector lever 90, and that the point detector lever is provided at its opposite end with a similar depending lug H12 (see Fig. 4) to which the roller 94 can be attached in the event that it is desired to have the switch point I normally closed instead of the switch point 2.

As is well understood, the contacts of a circuit controller of the type described are utilized to control signals governing traic over the associated switch, and their primary purpose is to cause the signals to indicate stop unless the switch points occupy their proper positions relative to the fixed rails and are properly locked in these positions. With the portion of the circuit controller thus far described, these contacts will adequately do this in all instances where the apparatus is in proper working order. However, if a train improperly trails the switch while it it locked in its normal position in the manner shown, a dangerous condition might possibly exist because, under these conditions, While the switch points will be displaced at the top an amount which would easily operate the point detector contacts of the circuit controller if the detector rod could be connected with the points at the top of the points, it is necessary for clearance reasons to connect the detector rod to the switch points some distance below the top of the points, where, due to the rolling of the points during the trailing, the amount of the movement may not be more than one-half of that occurring at the top of the points, and, furthermore, after a train has trailed the switch, the points will usually spring back toward their original positions a certain amount. As a result, the iinal displacement of the point detector rod'may be very little, if any, more than the displacement which would correspond to a maximum permissible opening of the closed switch point, which is the setting at which the point detector contacts become opened, while the opening of the closed point at the top may be sufficient to be extremely dangerous for subsequent high speed train movements. In order to insure that this dangerous condition will be detected, we provide latching mechanism so constructed that if a train trails the switch while it is locked, this latching mechanism will retain the circuit controller contacts in their closed positions until after they are subsequently released by a maintainer. Thus, even though the switch points spring back toward their proper positions after the train has trailed through the switch, the signals governing traffic over the switch will continue to display a restrictive indication until the maintainer releases the contacts of the circuit controller and permits them to return to their normal positions. It is assumed that before the maintainer does this, he will inspect the switch points, and, if damaged, repair them, thus guarding against a dangerous condition due to damaged switch points.

Referring now again to Figs. 2, 3, and 4, the latch mechanism just referred to comprises the previously referred to latch arm 93, the free end of which is provided with a latch dog 93a which cooperates with a latch catch I B5 having a screw threaded upper portion I05a which is adjustably screwed through aA tapped hole provided in a latching member |06 (see Fig. 3). The latch catch is also provided with a rectangular latch head o having its opposite sides cut away to form two notches I5c and I05d, and the latch catch is adapted to be locked, by means of a lock washer |01, and a jam nut |98 provided on the threaded portion Ia above the latching member IBS, in an adjusted position in which either the side of the latch head IIlSb containing the notch i050, or the opposite side, faces the latch dog. To facilitate adjusting the latching member, the upper `end of the threaded portion ia is provided with one or more saw kerfs for the reception of a screw driver.

The latching member |96 extends transversely of the casing II) directly above the intermediate portion of `the rocker arm '10, and is pivotally supported at its ends on a rod IIil mounted in upstanding lugs HI provided on the frame 55. A curved cam arm II2 extends toward the right from the latch member |09 and is provided adjacent its right-hand end with a cam face IIZa which cooperates, under certain conditions to be described presently, with the cam dog 'I3 carried by the lock bar 5I. The latching member IOS is constantly biased to rotate in a clockwise direction by means of the cam arm, and also by means of a spring I I3 which is stretched between a laterally projecting lug II4 provided on the frame and a spring arm H5 provided on the latching member.

The parts of the latching mechanism are so proportioned and the latch catch |115 is so adjusted that when the roller 84 on the point detector lever Si! is within the notch 9B in the point detector rod D, and the lock bar 5l occupies its locking position in which its left-hand end is within the notch 59 in the lock rod L, as shown in the drawings, the latch head |051) of the latch catch IE5 will engage the end of the latch dog 93a on the point detector lever 90 just above the notch 195e, and will thus prevent the latching member from rotating in a clockwise direction past the position in which it is shown in the drawings. It should be pointed out that the spring H3 materially aids in preventing vibration, and consequently, wear, between the latch catch and the latching dog when the parts are in the positions shown since the latch catch is normally held firmly againstv the end of the latching dog.

Bolted to the bottom wall of the casing I0 at the left-hand end of the casing directly above an opening H9 is an insulating terminal board l2!! provided with clamping means I2! for gripping double bond wires as well as with terminal screws for, the reception of conductors E22 by means of which the bond wire clamping means may be electrically connected with the terminal posts 86. Holes E23 are also provided in the terminal board E29 to enable line wires to be led chrectly to the terminal posts.

In explaining the operation of the circuit controller as `a whole, we shall first assume that the parts are in their normal positions in which they are shown in the drawings, and that the switch is moved to its reverse position by means of the hand-throw lever 3B in the manner previously described. Under these conditions, the movement of the lock bar 5l which takes place before the lock bar becomes completely withdrawn from the notch 59 in thelocl; rod L will cause the cam face 13a of the cam dog 13 'to engage the cam face H2a of the cam arm H2 and rotate the latch member 85 in ay counterclockwise direction, as viewed in Fig. 3, to a position in which the latch catch Hit is out of engagement with the latch dog 93a on latch arm 93, and will also cause the cam face 13a to engage the cam face 78a on the rocker arm 'l0 and rotate the rocker arm from its normal extreme position to its reverse eXtreme position, thereby closing the contacts 82-83.` The motion of the rocker arm 10 also lowers the finger i0! to such a position that when the switch points subsequently start to move and force the roller 94 out of the notch 95 in the lock rod, the point detector lever will be free to rotate without causing the rounded end IM) of the arm 99 of the point detector lever to engage the finger mi. The motion of the lock bar which takes place after they roller 94 has been forced out of the notch S6 in the-lock rod will cause the dog 'F3 to move past the cam face H2@ on the cam arm H2, and will thus permit the latching member IGS to rotate in a clockwise direction, as viewed in Fig. 3, to the position in which the cam arm l l2 on the latching member engages the top of the lugs 'F2 which support the pin ll, but the dog T3. will continue to engage the rocker arm lll during the balance of the movement of the lock bar and will thus retain the rocker arm in its reverse extreme position.

When the switch points have been moved to their reverse positions, and the hand-throw lever positions, the operation of the circuit controller will be substantially the reverse of that just described, it being noted that under these conditions, the latching member Will be rotated to the position in which the latch catch E05 is clear of the latch dog 93a by engagement of a cam face o provided on the cam dog 'I3 with the cam surface Ha on the latch arm H2, and will subsequently be retained in this position until after f the notch et in the point detector rod D moves into alignmentwith the roller gli by engagement of the top of the' dog with the cam surface ll2a. Inasmuch as the operation of the circuit controll-er during movement of the switch points to their normal positions is substantially the reverse of kthat which takes place during movement of the switch points to their reverse positions by the hand-throw lever, it is believed that this operation will be understood from an inspection of the drawings and from the foregoing description without further detailed description.

We shall now assume that the parts are in the positions in which they are shown in the drawings and that a train trails the switch. Under these conditions, the extreme forces which are exerted on the switch points by the trailing train will force the point detector rod D upwardly, as Viewed in Fig. 2, far enough to cause the roller 945 on the point detector lever to move out of the notch 96 in the point detector rod, and will thus cause the point detector leverto rotate in a clockwise direction as viewed in Fig. 3. This clockwise rotation of the point detector lever will act through the arm 99 and finger IBI to rotate the rocker arm 'm in a counterclockwise direction to its reverse eXtreme position, thus closing the contacts 82-83. This rotation of the point detector lever willA also cause the latch arm 93 to move downwardly to the position in which the lock dog 93a aligns with the notch i050 in the latch catch G05. The latch member l' will therefore now rotate, due to its bias, to the position in which the latch dog 93a enters the notch |050 in the latch catch H35. It will be apparent from an inspection of the drawings that when the latch dog 33a has once entered the notch m50, the point detector lever will be held in the position in which the roller 94 is out of the notch S5, and the rocker arm l@ will therefore be held in the position in which the contacts 82-83 are closed, until the latch catch is subsequently moved out of engagernent with the latch dog even if the point detector rod subsequently returns to the position in which the notch 96 aligns with the roller 94. It follows that inl order to release the contact operating member and permit the contacts 352-83 lto become opened after they have once been closed in the manner just described, it is necessary to restore the latching member |06 to its normal position in which it is shown in the drawings. This may be done either by removing the cover H and raising the cam arm H2 manually, or by throwing the switch movement by hand to its reverse position, in which latter case cam dog '53 will raise the cam arm H2 and will thus release the latch catch. When the p oint detector contacts are unlatched by operating the mechanism to its reverse position by hand, if the switch points have been disturbed at all by the trailing train, the roller Q4 on the point detector lever will not reenter the notch S6 in the lock rod when the switch is subsequently restored to its normal position, because the displacement of 75` k38 is operated to restore them to their normal the switch points will cause the lock rod to be out of adjustment, and as a result the plunger lock contacts will remain open, thus insuring that an indication of the damaged condition of the switch will be given.

An important feature of a switch operating mechanism embodying our` invention is that by properly assembling the parts, the same parts may be used for either a left-hand or a righthand switch layout regardless of whether the switch point adjacent the mechanism is normally closed or normally open. For example, the layout shown in Fig. 1 is a right-hand layout with the switch point adjacent the switch operating mechanism normally closed. If, now, with this layout, it is desired to have the switch point adjacent the mechanism normally open instead of normally closed, this result mayreadily be accomplished by turning the motion plate 25 end for end, rotating the target staff in a counterclockwise direction to the position in which the pin 51 on the target crank 63 enters the cam slot 65a in the motion plate, removing the switch operating arm 50a, from the switch actuating shaft 44 and rotating the switch actuating shaft in a clockwise direction, as viewed in Fig. l, through an angle of approximately 120 to the position in which the escapement crank is disposed at the opposite side of the mechanism, and then reassembling the operating arm on the switch actuating shaft in a position displaced 60 in a counterclockwise direction from the position shown in the drawings, and nally removing the roller 94 from the lug 95 on the point detector lever and attaching it to the lug |92.

For a left-hand layout, that is to say for a layout in which the switch operating mechanism is mounted on the left-hand side of the track when facing the switch points, if it is desired to have the switch point adjacent the mechanism normally open, the mechanism will be assembled in the manner shown in Figs. 2, 3, and 4 except for the fact that the shaft 3l will be turned end for end to cause the hand-throw lever 38 to be disposed at the outer side of the mechanism.

For a left-hand layout with the point adjacent the mechanism normally closed, the mechanism will be assembled in the manner described above for a right-hand layout with the point adjacent the mechanism normally open, except for the fact that the shaft 3l will be turned end for end to cause the hand-throw lever to be disposed at the outer side of the mechanism.

A mechanism embodying ur invention may be used to operate both a single switch and a derail by merely connecting the pipe line which operates the derail with the lock bar 5l in the manner shown diagrammatically in Figs. 1G and 11.

Under some conditions of operation, it is desirable to enforce a certain sequence of operation between two mechanisms embodying our invention which mechanisms are used to operate two switches at the opposite ends of a crossover between the main track and a siding. When this is the case, it is necessary to replace the lock bar shown in Figs. 2 and 3 with what is commonly referred to as a loose lock bar. Such a lock bar is shown in Figs. 8 and 9 from which it will be noted that this latter lock bar, which is designated by the reference character H5, is not provided with any driving stud, but is provided with an upstanding dog I |5a and with a recess H51) adjacent the left-hand end of the dog I I5a. The

dog I I5a and recess |I5b are adapted to cooperate with a projecting arcuate lug 30a which is provided on the segment gear 30, to prevent movement of the segment gear except when the lock bar is moved to the right to a position in which the switch is unlocked, and in order to cause the segment gear to properly cooperate with the loose lock bar, it is necessary to reverse the position of the segment gear 30 with respect to the shaft 3| in the manner shown in Figs. 8 and 9. When the segment gear is assembled in this manner, the lug 30a extends over the lock bar H5 and cooperates with the recess H51; and dog HELL in such manner that when the switch is locked by means of the lock bar, the lug 30a will engage the top of the dog and prevent operation of the hand-throw lever away from its normal position, but that, when the switch is unlocked, the lug will enter the recess Il5b, and will permit operation of the hand-throw lever.

A layout using a pair of mechanisms, one of which employs a loose type of lock bar, for operating the two switches at the ends of a crossover between a main track and a siding is shown diagrammatically in Figs. 12 and 13, and a layout employing two mechanisms both equipped with loose lock bars for operating the two switches at the ends of a crossover between two main tracks is shown diagrammatically in Figs. 14, l5, and 16. It will be noted that in the layout shown in Figs. 14, 15, and 16, the lock bars H5 of the mechanisms which operate the switches are independently operated from a separate stand located intermediate the two movements.

It should be pointed out that the segment gear 3U is so constructed that when the motion plate driven type of lock bar is used, it will be impossible to operate the movement unless the hub of the segment gear 30 is placed over the lock bar, as shown in Fig. 2, whereas, when the loose type of lock bar is used, it will be impossible to operate the movement unless the segment gear is assembled in the opposite manner as shown in Figs. 8 and 9. This construction insures that the mechanism will always be assembled in the proper manner.

Although we have herein shown and described only two forms of railway switch operating mechanisms embodying our invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. A switch operating mechanism comprising a casing, a motion plate, means for mounting said motion plate in said casing for movement longitudinally of the casing in such manner that said motion plate can be turned end for end, means for reciprocating said motion plate, means driven by the motion plate for operating a switch, a transverse slot in each end of said motion plate, a lock rod extending into said casing and movable with the switch, a lock bar slidably mounted in said ,casing in removable guides and cooperating at one end with said lock rod, and a stud on said lock bar adapted to enter one or the other of said slots in said motion plate to provide a driving connection between said motion plate and said lock bar, the parts being so proportioned that said stud` will be held in operative engagement with one or the other of said slots when said guides are in place.

2. In combination, a railway switch, a lock rod connected with the switch points to move therewith and provided with a notch, a lock bar, means for at times moving said lock bar into the notch in said look rod to lock the switch points in one extreme position and for vat other times withdrawing said lock bar from said notch to unlock the switch points, a contact, means for operating said Contact whenever said lock bar is withdrawn from said notch, a point detector rod connected with the switch, means operated by said detector rod for operating said contact if the switch points are displaced from said one position while they are locked and for latching said contact in its operated position, and means eiective if said lock bar is withdrawn from the notch in said lock rod when said contact is latched in its operated position for unlatching said contact.

3. In combination, a switch, a lock rod connected to the switch to move therewith, a lock bar movable between a locking and an unlocking position and eiective when in its locking position for engaging said lock rod to lock said switch in one extreme position, means for moving said lock bar, a contact operating memberbiased to one position, a rocker arm connected at one end with said contact operating member, means carried by said lock bar and cooperating with said rocker arm for moving said contact operating member from its one position to its other position whenever said lock bar is movedto its unlocking position, a point detector rod secured to the switch and provided with a notch, a pivoted point detector lever provided with a roller and biased to a position in which said roller enters said notch, means on said point detector lever engaging means carried by said rocker arm for actuating said rocker arm to move said contact operating member from its one position to its other position whenever said roller is forced out of said notch; and a contact controlled by lsaid Contact operating member.

4. In combination, a switch, a lock rod connected to the switch to move therewith, a lock bar movable between a locking and an unlocking position and effective when in its locking position for engaging said lock rod to lock said switch in one extreme position, means for moving said lock bar, a' contact operating member biased to one position, a rocker arm connected at one end with said contact operating member, means carried by said lock bar and cooperating with said rocker arm for movin-g said contact operating member from its one position to its other position whenever said lock bar ismoved to its unlocking position, a point detector rod secured to the switch and provided with a notch, a pivoted point detector lever provided with a roller and biased to a position in which said roller enters said notch, means on said point detector lever engaging means carried by said rocker arm for actuating said rocker arm to move said contact operating member from its one position to its other position whenever said roller is forced out of said notch; a Contact controlled by said contact operating member, a latch arm secured to .said point detector lever, a pivoted latching member biased to a latching position and provided with means for engaging said latch arm when said roller is forced out of said notch and said latching member occupies its latching position to latch said contact operating member in its other extreme position, and means on said latching member for preventing said latching member from moving to its latching position when said lock bar is moved to its unlatching position.

5. A switch operating mechanismv comprising a casing, a motion plate, means for mounting said motion plate in said casing for movement longitudinally of the casing in such manner that said motion plate can beturned end for end, means for reciprocating said motion plate, means driven by the motion plate for operating a switch, a camslot formed in eachend of said motion plate, a target staff mounted in said casing, and means on said target staff adapted to enter one or the other of said cam slots to provide a driving connection between said motion plate and said target staff in either position of the motion plate.

6. A switch operating mechanism comprising a casing, a motion plate, means for mounting said motion plate in said casing for `movement longitudinally of the casing in such manner that said motion plate can be turned end for end, means for reciprocating said motion plate, means driven by the motion plate for operating a switch,

a cam slot formed in each end of said motion plate, a target stai mounted in said casing, and a crank securedto said target stai and adjustable to different angular positions with respect to saidl staiT and cooperating with one or the other of said cam slots to provide a driving connection between said'motion plate and said target staff in either position of the motion plate.

HERBERT L. BONE. KENNETH J. J. MCGOWAN.v 

